Meconium-Stained Amniotic Fluid and the Meconium Aspiration Syndrome

Continuous positive airway pressure and conventional mechanical ventilation in the treatment of meconium aspiration syndrome

“…9 Multiple investigations in both animals and humans have shown the deleterious effects of meconium on endogenous surfactant. [12][13][14] Meconium may inhibit surfactant production, displace surfactant from the alveolar surface and decrease its surface tension lowering function. Surfactant inhibition is concentration dependent and results from a variety of toxic biochemical effects of the meconium constituents.…”

The role of complement in meconium aspiration syndrome

“…7 Although the controversies still remain in the literature as to what extent meconium per se leads to MAS, 8,9 increasing evidence indicates that the inflammation induced by meconium is an essential part of the pathophysiology. 7,10 The assumed chemical pneumonitis caused by meconium was first documented in rabbits by infiltration of polymorphonuclear leukocytes in alveolar septa within 6 h after instillation of meconium, 11 and a later study documented increased counts and chemotactic activity of neutrophils in lung lavage fluid from pigs. 12 Leukocytes are important sources for three main inflammatory branches that are induced or activated by meconium: cytokines, arachidonic acid metabolites and reactive oxygen species.…”

Meconium aspiration syndrome: historical aspects

“…The meconium aspiration syndrome (MAS), associated with aspiration or perhaps diffusion of meconium into the fetal airways, occurs in about 5% of these infants. 3,4 Meconium aspiration syndrome is defined as respiratory distress in an infant born through MSAF whose symptoms cannot be otherwise explained. Aspirated meconium can interfere with normal breathing by several mechanisms.…”

“…Cleary and Wiswell 3 have proposed severity criteria to define MAS: (1) mild MAS is disease that requires less than 40% oxygen for less than 48 h, (2) moderate MAS is disease that requires more than 40% oxygen for more than 48 h with no air leak and (3) severe MAS is disease that requires assisted ventilation for more than 48 h and is often associated with persistent pulmonary hypertension. Of infants in whom the MAS develops, more than 4% die, accounting for 2% of all perinatal deaths.…”